Disintegrating training ammunition for firearms



Feb. 23, 1965 w. JUNGERMANN ETAL 3,170,405

DISINTEGRATING TRAINING AMMUNITION FOR FIREARMS Filed Febi 7, 1963 2 Sheets-Sheet 1 Feb. 23, 1965 W. JUNGERMANN ETAL DISIN'I'EGRATING TRAINING AMMUNITION FOR FIREARMS Filed Feb. 7, 1963 2 Sheets-Sheet 2 llllllflll v\\\\\\\\\\ Jig/3 DISINTEGRATMG TRAINING AMMUNITION FtDR FHQEARMS Werner Jungermann, Karlsrnhe, Baden, Rudolf Niemann, Mulheim, Baden, Ludwig Six, Karlsruhe, Baden, and Willi Walther, .lohlingen, Baden, Germany, assignors to Industrie-Werlre Karlsruhe Aktiengesellschaft, Karisruhe, Germany Filed Feb. 7,1963, Ser. No. 256,919

Claims priority, application Germany, Mar. 17, 1962,

'2 Claims. (Cl. 102-91) The invention relates to a practice or training ammunition for firearms and particularly to a disintegrating bullet with a guide band for machine guns and single round guns, which is formed from a material which possesses the required mechanical stiffness in the barrel and breaks up on leaving the barrel, the bullet section consisting of a front part and rear part, with a pressing of metal powder. With disintegrating ammunition the recoil should, as is known, be the same as with normal firing so that the kinematics of the whole action and guidance system shall function in the same Way. Also the wear of the action and of the tube should be as small as possible and the strength of the cartridge and the bullet should be such that, as regards their stiffness, there shall be no permanent changes in shape or damage thereto or to the belt links.

Bullets for practice cartridges are known which consist of two similar halves of a synthetic resin capsule. The capsule is filled with a pressing of metal powder. [The two parts of the capsule can be produced comparatively easily, but the'strength at the joint between the two capsule sections is not sufficiently high 'to ensure a satisfactory break up of the capsule and satisfactory disintegration of the metal powder; moreover, the capsule'is not guided in the barrel.

In order to obtain a useful and easily disintegrating practice cartridge the invention is characterized in that the joining contact surfaces of the front and rear parts of the bullet, considered in section, have a fiat surface (cone) inclined towards the central axis, an S-shaped line or a threaded line, whereby the contact surfaces, seen from the bottom of the bullet, lie in front of or beneath one United States Patent ice g... Fe, 19.5

walls of equal strength; thereby the disintegrating action is maintained and even the amount of powder necessary ballistically is substantially reduced. By the connection of the two halves'of the bullet by means of threads it is possible, moreover, to use both normal and also rolled threads, with cylindrical or conical threads.

Further details are set out in the following description of preferred embodiments, in conjunction with the accom panying drawings, wherein:

FIG. 1 shows a bullet body in which the two parts of the bullet are joined by means of cones and the guide band lies over the cones, l

FIG. 2 shows the same construction as FIG. 1, but with a sealing flange in front of the bottom of the bullet,

FIG. 3 shows a front part of the bullet with longitudinal ribs up to the commencement of the cone, 1

FIG. 4 shows a section on the line IVIV of FIG. 3,

FIG. 5 shows a bullet with a longer bullet front part than in FIGS. 1 and 2, wherein the cones lie vnear the bottom of the bullet,

FIG. 6 shows the same arrangement as FIG. 5 only with a sealing flange at the bullet bottom,

. FIG. 7 shows a bullet with a spreader disc at the sealing flange,

FIG. 8 shows the bottom of a bullet with an enlarged bottom diameter,

FIG. 9 shows a bullet with a curved bullet bottom,

FIG. 10 shows a bullet body in which the two halves of the bullet are joined by means of rolled or knurled threads with a sealing flange in front of the bullet bottom,

FIG. 11 shows a further threaded connection wherein the connection is effected near the bullet bottom,

FIG. 12 shows a construction with conical threads and a sealing surface in front of the bullet bottom,

FIG. 13 shows a construction with normal threads and a sealing flange in front of the bullet bottom, and

FIG. 14 shows the contact surfaces between the bullet front part and rear part as an S-line in section.

of the sealing guide bands, one,-two or more of which may be provided on the body of the bullet. Thereby the 1 contact surface of the front part of the bullet lies on that of the rear part of the bullet. The cones which may be smooth or grooved or corrugated, are fixedly connected together by means of a suitable adhesive; smooth contact surfaces can also be joined by frictional welding. increasing the mechanical stiffness the front part of the bullet may be provided with longitudinal ribs or comprises longitudinal grooves for reducing the breakage strength against internal excess pressures, which extend up to the commencement of the contact surfaces of the front part of the bullet or even as far as the cone. Furthermore, the device is such that, besides the sealing guide band on the front part of the bullet, a sealing flange is included as an additional guide at the rear part extending beyond the bottom of the bullet.

By this construction of the disintegrating bullet, satisfactory breakdown of the metal powder pressing is permitted, whereby the mechanical strength of the bullet body inside the barrel is so great that no preliminarybursting of the pressing results. Moreover, the sealing and guiding of the bullet body is substantially improved as compared with previous constructions, since the cone, 8- shaped, or threaded connection has the advantage that air inclusions are avoided and the outer surfaces to be joined are pressed together under pressure; thereby a satisfactory joint is obtained. Further, no stiffening of the walls occurs, as is, for example, the case with two cylindrical For I The wall parts of the disintegrating bullet of a practice cartridge according to theinvention is formed from two parts 1 and 2 which fittightly one upon the other by means of their contact surfaces 1a and 2a. The contact surfaces la of the front part 1 of the bullet thus-provide a coned socket which engages a coned spigot 2a of the rear part 2 of the bullet. The wall consists of a material which has a sufliciently great strength or stiffness in the barrel of the firearm but breaks apart on leaving the barrel. This may be a synthetic resin, a pressing material, wood fibre or the like. In some cases the front part of the bullet can also be provided with longitudinal ribs or with longitudinal grooves 3 (FIGS. 3 to 7) for increasing the flexure stiffness or for reducing the breakage strength against internal excess pressure, which extend up to the beginning of the cone at the front part of the bullet, or extend also on along the cone.

A guide band 4 is arranged on the outer wall of the front part of the bullet for a drawn barrel. FIG. 11 shows a front partof a bullet with two guide bands. In some cases further guide bands may be desirable with a still longer bullet body. The contact surfaces can, as seen from the bottom 5 of the bullet, lie in front of the guide band (FIGS. 5 to 7). The arrangement can also be such that they lie under the guide band of the bullet I (FIGS. '1, 2 8-13). ,By the latter arrangement in par- 3 ticular, a. very satisfactory sealing between the two parts of the bullets is obtained. For further sealing and for satisfactory guiding of the bullet in the grooves of the barrel, and thus for firm adherence of the two halves of the bullet, the rear part of the bullet comprises, besides the sealing guide band on the front part of the bullet, a sealing flange 6 as an additional guide (FIGS. 2, 6, 10, 12, 13) extending beyond the bottom of the bullet, the outer diameter of which is the same as or greater than that of the bullet guide band.

FIG. 7 shows an embodiment in which the sealing flange is preferably equal to the diameter of the bore of the neck portion 7 of the casing surrounding it; in this case a spreader disc 8 is introduced into the sealing flange which is forced forwardly against the bottom of the bullet by the powder gas on firing. Thereby the sealing flange is pressed outwardly into the grooves of the barrel so that also in this case, as in the embodiment according to FIGS. 2, 6, 10, 12 and 13, satisfactory guiding in the barrel of the weapon is obtained by the sealing flange H and by the guide band and good sealing between the two parts of the bullet.

Finally (FIG. 8), the bottom of the bullet may have a greater diameter than the bore of the neck of the casing 7 to increase the extraction resistance of the bullet from the case. The same result is obtained if the bottom of the bullet is curved downwardly (FIG. 9) and the pressure of the powder gas presses the latter forwardly at the rear and towards the side. A hollow space is provided internally of the bullet between the bottom and the metal powder pressing, in the position of rest. When the gas pressure increases in the cartridge case, first the bottom of the bullet is pressed to a flat form from the outwardly curved position. Thereby its outer diameter increases and forms a neck which is pressed by the gas pressure against the narrow neck of the cartridge case. Thereby the necessary high extraction force is obtained.

What we claim is:

1. A projectile for practice ammunition adapted for firearms, said projectile comprising an elongated disintegrating bullet formed of two parts, one part consisting of a hollow cylindrical base member of uniform exterior diameter closed at one end and open at its other end, said last named other end being provided with an outer conical surface, the other part of said bullet consisting of a hollow nose member provided with a hollow cylindricalportion of the same exterior diameter as said base member, said hollow cylindrical portion having its open end provided with an inner conical surface which engages tightly the outer conical surface on said hollow cylindrical base member, said inner conical surface being surrounded by an outwardly projecting cylindrical guide band formed integrally with said hollow nose member, said nose member having at its closed end a flat surface which merges with a circumferential convex wall into the cylindrical portion of said nose member, said united base member and nose member providing a single chamber therein having substantially the same diameter from the base member to the convex wall portion of said nose member, and a core formed of metal powder having the shape of said chamber contained within said chamber.

2. A projectile for practice ammunition adapted for firearms, said projectile comprising an elongated disintegrating bullet formed of two parts, one part consisting ,of a hollow cylindrical base member of uniform exterior diameter closed at one end and open at its other end, said last named other end being provided with an outer conical surface, the other part of said bullet consisting of a hollow nose member provided with a hollow cylindrical portion of the same exterior diameter as said base member, said hollow cylindical portion having its outer open end provided with an inner conical surface which engages tightly the outer conical surface on said hollow cylindrical base member, said inner conical surface being surrounded by an outwardly projecting cylindrical guide band formed integrally with said hollow nose member, said nose member having at its closed end a small flat central surface which merges with a circumferential convex wall into the cylindrical portion of said nose member, said united base member and nose member providing a chamber therein having substantially the same diameter from the base member to the convex wall portion of said nose member, and a core formed of metal powder having the shape of said chamber contained within said chamber, the entire interior wall surface of said hollow nose member being provided with closely spaced longitudinally extending grooves for reducing the breakage strength of the nose member and facilitating disintegration of the same immediately after the bullet has been projected.

References Cited by the Examiner UNITED STATES PATENTS 590,428 9/97 Bennett 102-38 911,591 2/09 Hoxie 102-91 1,149,830 8/15 Hoagland 102-91 2,304,152 12/42 Darden 102-52 2,345,619 4/44 Moore 102-92.5 2,365,708 12/44 Landen et al. 102-52 2,411,862 12/46 Arnold 102-67 2,991,718 7/61 Ferguson 102-91 3,000,309 9/61 Zapf 102-67 3,019,733 2/62 Braid 102-91 3,022,734 2/62 Kidder 102-95 FOREIGN PATENTS 459,590 4/ 35 Great Britain.

776,005 10/34 France. 1,147,250 10/58 France.

264,944 2/50 Switzerland.

BENJAMIN A. BORCHELT, Primary Examiner. 

1. A PROJECTILE FOR PRACTICE AMMUNITION ADAPTED FOR FIREARMS, SAID PROJECTILE COMPRISING AN LEONGATED DISINTEGRATING BULLET FORMED OF TWO PARTS, ONE PART CONSISTING OF A HOLLOW CYLINDRICAL BASE MEMBER OF UNIFORM EXTERIOR DIAMETER CLOSED AT ONE END AND OPEN AT ITS OTHER END, SAID LAST NAMED OTHER END BEING PROVIDED WITH AN OUTER CONICAL SURFACE, THE OTHER PART OF SAID BULLET CONSISTING OF A HOLLOW NOSE MEMBER PROVIDED WITH A HOLLOW CYLINDRICAL PORTION OF THE SAME EXTERIOR DIAMETER AS SAID BASE MEMBR, SAID HOLLOW CYLINDRICAL PORTION HAVING ITS OPEN END PROVIDED WITH AN INNER CONICAL SURFACE WHICH ENGAGES TIGHTLY THE OUTER CONICAL SURFACE ON SAID HOLLOW CYLINDRICAL BASE MEMBER, SAID INNER CONICAL SURFACE BEING SURROUNDED BY AN OUTWARDLY PROJECTING CYLINDRICAL GUIDE BAND FORMED INTEGRALLY WITH SID HOLLOW NOSE MEMBER, SAID NOSE MEMBER HAVING AT ITS CLOSED END A FLAT SURFACE WHICH MERGES WITH A CIRCUMFERENTIAL CONVEX WALL INTO THE CYLINDRICAL PORTION OF SID NOSE MEMBER, SAID UNITED BASE MEMBER AND NOSE MEMBER PROVIDING A SINGLE CHAMBER THEREIN HAVING SUBSTANTIALLY THE SAME DIAMETER FROM THE BASE MEMBER TO THE CONVEX WALL PORTION OF SAID NOSE MEMBER, AND A CORE FORMED OF METAL POWDER HAVING THE SHAPE OF SAID CHAMBER CONTAINED WITHIN SAID CHAMBER. 